A Frequency Stable Vacuum-Sealed Tube High-Power Microwave Vircator Operated at 500 Hz

Author

Parson, Jonathan M. ; Lynn, Curtis F. ; Scott, Mike C. ; Calico, Steve E. ; Dickens, James C. ; Neuber, Andreas A. ; Mankowski, John J.

Author_Institution

Dept. of Electr. & Comput. Eng., Texas Tech Univ., Lubbock, TX, USA

Volume

36

Issue

5

fYear

2015

fDate

May-15

Firstpage

508

Lastpage

510

Abstract

Operation of repetitive high-power microwave (HPM) sources is predominantly limited by thermal properties of anode and cathode materials. This letter presents a reflex-triode virtual cathode oscillator (vircator) capable of operating at 500 Hz at current densities between 100-200 A/cm² for multiple burst durations of 1-2 s. Stable vircator operation under such a thermally punishing environment is facilitated by the use of a thin pyrolytic graphite anode. The results presented focus on two anode-cathode (A-K) gap spacings: 11 and 21 mm, which produce stable microwave radiation at 4.6 and 1.6 GHz, respectively. Characteristic voltage, current, and microwave waveforms in conjunction with short-time Fourier transforms, frequency spectrographs, and HPM power density data for 1000 and 500 pulses at 1.6 and 4.6 GHz, respectively, are presented.

Keywords

Fourier transforms; anodes; cathodes; current density; graphite; triodes; vircators; C; Fourier transforms; anode materials; anode-cathode gap spacings; cathode materials; current density; frequency 1.6 GHz; frequency 4.6 GHz; frequency 500 Hz; frequency spectrographs; frequency stable vacuum sealed tube; high power microwave vircator; microwave radiation; multiple burst durations; reflex-triode virtual cathode oscillator; repetitive high power microwave sources; thermal properties; thermally punishing environment; thin pyrolytic graphite anode; Anodes; Cathodes; Density measurement; Electron tubes; Materials; Plasmas; Power system measurements; Anodes; Carbon fiber; Cathodes; Electron beam; High power microwave generation; Pyrolytic graphite; Vircator; carbon fiber; cathodes; electron beam; high power microwave generation; pyrolytic graphite; vircator;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2015.2408216

Filename

7052371